Zipper construction

ABSTRACT

A zipper construction includes first and second fabric pieces. Each of the first and second fabric pieces includes an inner edge to which teeth are affixed. The first and second fabric pieces are formed of a weave defined by pre-dyed warp fibers formed of a substantially inelastic material and weft fibers that are formed of an elastic material. The zipper construction also includes a slider that engages the teeth of the first and second fabric pieces.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims the benefit of U.S. patent application Ser. No. 60/940,097, filed May 25, 2007, which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

The present invention relates generally to zippers and more particularly, to a zipper construction that has stretch in a transverse direction of the zipper.

BACKGROUND

A conventional zipper is stitched on two fabrics (a side lining) and the fabrics are stitched on a number of different articles, such as clothing articles, bags (purses), luggage, shoes, or the like. Conventional fabrics that are used to form the fabric pieces of the zipper suffer from the disadvantage that the fabrics are essentially inelastic in the transverse direction (transverse extension force exerted on the fabrics along an orientation substantially perpendicular to the elongated orientation of the zipper). In the case of an overloaded piece of luggage/purse or overstretched clothing due to weight gain (either expected gain as in a pregnancy or unexpected and undesired as in obesity). Once zipped up, the zipper can easily burst open when the side lining (fabric pieces) is stretched outwards by the overloaded baggage/purse or overstretched clothing causing damage to the article and potential loss of items in the baggage/purse and embarrassment as when the article is clothing and it separates along the zipper.

While a number of attempts have been offered to solve the above problem, each of these attempts has associated disadvantages. For example, U.S. patent application publication No. 2005/0066485 discloses a side lining for zippers that is mainly made up of an elastic, woven belt-like piece attached to both lateral sides of a zipper. However, by affixing the zipper's teeth to a woven, elastic material (fabric), the teeth are prone to being pulled apart and disengaged from one another when the article in which the zipper is incorporated is stretched along the transverse direction (e.g., as when a bag is overloaded or when a person experiences weight gain). The disengagement of the zipper's teeth results in an inoperative zipper and can result in opening of the article.

Other zipper constructions that aim to provide or allow some degree of transverse stretch similarly suffer from disadvantages and do not provide an acceptable product that allows for a degree of transverse stretch to allow for added weight or overstuffed luggage.

SUMMARY

A zipper construction according to one embodiment includes first and second fabric pieces. Each of the first and second fabric pieces includes a first region to which teeth are affixed and a second region that is adjacent the first region. The first region is formed of a substantially inelastic material and the second region is formed of an elastic material. Each of the first and second pieces is constructed so that there is a seamless transition from the first region to the second region and the fabric piece is elastic in a transverse direction relative to a length of the fabric piece. The zipper also includes a slider that engages the teeth of the first and second fabric pieces.

In another embodiment, a zipper construction includes first and second fabric pieces. Each of the first and second fabric pieces includes an inner edge to which teeth are affixed. The first and second fabric pieces are formed of a weave defined by pre-dyed warp fibers formed of a substantially inelastic material and weft fibers that are formed of an elastic material. The zipper construction also includes a slider that engages the teeth of the first and second fabric pieces.

A method for manufacturing a zipper construction includes the steps of: (1) pre-dyeing warp fibers that are formed of a substantially inelastic material; (2) introducing the pre-dyed warp fibers into a fabrics loom; (3) introducing elastic weft into the fabrics loom under substantially constant weft tension; (4) weaving the warp and weft fibers into a colored zipper tape such that the zipper tape includes at least 20% of the elastic weft, the zipper tape having increased stretch in a transverse direction due to the elastic weft being removed from the pre-dyeing step; (5) attaching coils along an inner edge of the zipper tape, the coils representing teeth; and (6) aligning two pieces of zipper tape with their inner edges facing one another and engaging a slider with the coils.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

The foregoing and other features of the present invention will be more readily apparent from the following detailed description and drawings of illustrative embodiments of the invention in which:

FIG. 1 is a top plan view of a zipper construction according to one embodiment of the present invention;

FIG. 2 is a top plan view of a zipper construction according to a second embodiment of the present invention; and

FIG. 3 is a close-up of a weave pattern for the tape of the zipper construction of FIG. 2.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Now referring to FIG. 1, a zipper construction 100 according to one exemplary embodiment of the present invention. The zipper construction 100 includes two strips of fabric 110, 120, which can also be referred to as fabric tape. Each of the strips of fabric 110, 120 is affixed to one of the two pieces to be joined. For example, in the case of an article of clothing, one fabric strip 110 is attached to one clothing panel and the other fabric strip 120 is attached to another clothing panel that is to be joined to the one clothing panel. The fabrics strips 110, 120 carry tens or hundreds of specially shaped metal or plastic teeth. The zipper construction 100 also includes a slider 200 that is operated by hand and moves along the rows of teeth 210. Inside the slider 200 is a Y-shaped channel that meshes together or separates the opposing rows of teeth 210, depending on the direction of the movement of the slider 200. The zipper construction 100 also includes stoppers 230 at the two ends of the teeth 210 that serve to restrict the longitudinal (up and down) movement of the slider 200.

In accordance with the present invention, the zipper construction 100 is designed so as to offer stretch in the transverse direction of the zipper 100 (a direction that is substantially perpendicular to the elongated orientation of the zipper). More specifically, each fabric strip 110, 120 includes a first region 130 that includes the teeth 210 and extends a predetermined distance outward from the teeth 210 and a second region 140 that is adjacent and integral with the first region 130. In other words, the teeth 210 are affixed to the first region 130 of the zipper 100, while the second region 140 is a region that surrounds the first region 130. Both the first and second regions 130, 140 extend the length of the complete zipper 100 in the longitudinal direction thereof.

The first region 130 is formed of a material that is substantially inelastic (rigid) so that the fabric strip in this region is essentially inelastic in the transverse direction (a side to side direction that is perpendicular to the longitudinal zipper direction) (identified by the arrows A in FIG. 1). Once again, it is this region 130 that carries the teeth 210 and therefore, it is desirable for this region to be inelastic (rigid) so that the teeth 210 of the two strips 110, 120 remain engaged even when experiencing a transverse extension force exerted on the zipper 100 along an orientation substantially perpendicular to the elongated orientation of the zipper 100.

Any number of materials can be used to make the first region 130 of each fabric strip 110, 120 so long as the material is at least substantially inelastic in the transverse direction. For example, the first region 130 can be formed of natural or synthetic materials, such as a 100% cotton material, a nylon material or a cotton and nylon blend or other inelastic synthetics, such as polyester. It will be appreciated that each of these materials is substantially or completely inelastic in the transverse direction. It will be understood that other materials can be used so long as the materials have the above property.

The second region 140 has different stretch properties (elasticity) relative to the first region 130 of the strip 110, 120 and in particular and unlike the first region 130, the second region 140 does have a degree of elasticity (stretch) in the transverse direction across the zipper to accommodate transverse stretching of the article in which the zipper is incorporated. By incorporating an elastic material into each strip 110, 120, while at the same time maintaining a rigid, inelastic strip portion immediately surrounding the teeth 210, the zipper 100 can stretch in the transverse direction when this type of transverse force is applied as occurs when baggage is overloaded or the wearer is too big for an article of clothing or shoes, etc.

The width of the first region 130 will be relatively small compared to the width of the second region 140 since the overall zipper construction 110 is intended to have transverse stretch. The width of the first region 130 is selected such that the teeth 210 remain engaged with one another even when the second region 140 is stretched transversely. This ensures proper operation of the zipper 100 even when it is subjected to a transverse force.

Any number of materials can be used to make the second region 140 of each fabric strip 110, 120 so long as the material is at least substantially elastic in the transverse direction. For example, the second region 140 can be formed of a blend of synthetic materials or a blend of natural and synthetic materials. In one embodiment, the second region 140 is formed of a blend of cotton and elastic fibers, such as spandex or elastane which is a synthetic fiber known for its exceptional elasticity (stretchability). These elastic fibers are stronger and more durable than rubber (a non-synthetic material). The material is commercially available under the trade name LYCRA® (LYCRA® branded fibers and fabrics). The amount of elastic fibers (LYCRA® fibers) in the blend can vary depending upon the desired stretch properties that are to be incorporated into the article. However, in one embodiment, the second region 140 has at least 10% LYCRA® fibers and in another embodiment, the second region 140 has at least 20% LYCRA® fibers and in another embodiment, the second region 140 has between about 25% to about 50% LYCRA® fibers. It will be appreciated that other brand fibers can be used in place of LYCRA® fibers so long as they exhibit the same or similar elastic properties.

Further, LYCRA® fibers come in different powers different degrees of elasticity- and therefore, this is another parameter that can be selected in order to tailor the properties of the zipper 100.

The second region 140 can also be a blend of synthetic inelastic fibers and elastic fibers. For example, the second region 140 can be formed of a blend of nylon and LYCRA® fibers or a blend of cotton, nylon and LYCRA® fibers. It is further contemplated that some types of latex can be used as the elastic component of the second region 140.

The resulting second region 140 exhibits elastic stretch in the transverse direction due to the presence of the elastic fibers and the second region 140 is formed using conventional fabric forming techniques, such as weaving or the like, so that the elastic fibers are oriented in a manner that imparts transverse stretch to the entire second region 140.

In accordance with the present invention, each fabric strip 110, 120 is formed so that it has a seamless transition from the first region 130 to the second region 140. In other words, the two regions 130, 140 are not two separate fabric pieces that are stitched along their edges; but instead, weaving techniques or other fabric fabrication techniques can be used to form the first region 130 and the second region 140 as a single integral strip with an interface, identified at 150, between the two regions 130, 140. This interface 150 can mark a transition from one weave pattern (first region 130) to a second, different weave pattern. In addition, the interface 150 defines the boundary between regions formed of different materials. It will be understood that since the two regions 130, 140 are formed of different materials, the weave pattern for each pattern may remain the same or in another embodiment, the weave patterns can be different so as to impart the desired degree of elasticity in the transverse direction across the zipper.

Depending upon a number of parameters, such as materials used and the amount of elastic fibers used, and the relative dimensions (widths) of the regions 130, 140, the amount of stretch in the transverse direction can either be modest to extreme (e.g., ½ inch to 3 inch), thereby adding a functional dimension to the zipper. For example, soft nylon luggage or knapsacks or duffels can have an additional 1″ to 3″ of “squeeze room” and be significantly easier to close if somewhat overpacked. The same is true for articles of clothing and footwear (shoes, sneakers, boots), etc. For example, evening gowns and other back zip dresses would be more comfortable to put on or try on and would have “room” for the wearer's body variations or weight fluctuations. Pants that are conventionally rigid would fit with a comfort function. Trying an article of clothing on in a dressing room would be significantly facilitated.

Now turning to FIGS. 2-3, a zipper construction 300 according to a second exemplary embodiment of the present invention. The zipper construction 300 includes two strips of fabric 310, 320, which can also be referred to as fabric tape. Each of the strips of fabric 310, 320 is affixed to one of the two pieces to be joined. For example, in the case of an article of clothing, one fabric strip 310 is attached to one clothing panel and the other fabric strip 320 is attached to another clothing panel that is to be joined to the one clothing panel. The fabrics strips 310, 320 carry tens or hundreds of specially shaped metal or plastic teeth 400. The zipper construction 300 also includes a slider 410 that is operated by hand and moves along the rows of teeth 400. Inside the slider 410 is a Y-shaped channel that meshes together or separates the opposing rows of teeth 400, depending on the direction of the movement of the slider 410. The zipper construction 300 also includes stops 420 at the two ends of the teeth 400 that serve to restrict the longitudinal (up and down) movement of the slider 410. More particularly, there are two top stops 420 that restrict upward movement of the slider 410. At a bottom end of one row of teeth 400 (e.g., teeth that are part of the right tape 320), there is a box (not shown) as is known in the zipper industry and at a bottom end of the other row of teeth 400 (left tape 310), there is a pin (not shown) that mates with the box.

In accordance with the present invention, the zipper construction 300 is designed so as to offer stretch in the transverse direction of the zipper 100 (a direction that is substantially perpendicular to the elongated orientation of the zipper). More specifically, each fabric strip 310, 320 includes a first (inner) edge 330 that includes the teeth 400 and an opposite second (outer) edge 332 that represents an edge of each strip (tape) 310, 320 which is attached to an object (carrier) of which the zipper construction 300 is a part of. For example, when the zipper construction 300 is intended to be attached to an article of clothing, such as a pair of pants or a shirt, jacket, etc., the strips 310, 320 are attached to the two edges of fabric. However, it will be appreciated that the zipper construction 300 can be used in other applications, such as luggage and other bags, sporting goods, camping gear (e.g., tents and sleeping bags), and other daily use items. As is known, zippers can: increase the size of an opening to allow the passage of objects, as in the fly of pants or in a pocket; join or separate two ends or sides of a single garment, as in the front of a jacket; and attach or detach a separable part of the garment to or from another, as in the conversion between trousers and shorts or the connection/disconnection of a hood and a coat.

In the illustrated embodiment, the zipper construction 300 is a coil zipper in which the slider 410 runs on two coils 400 on each side; the “teeth” are the coils. Two basic types of coils are used: one with coils in spiral form, usually with a cord running inside the coils; the other with coils in ladder form, also called the Ruhrnann type. Coil zippers are typically made of polyester coil and are thus also known as polyester zippers.

The term “single tape width” refers to a width of one of the strips 310, 320 and is identified by the legend C in FIG. 2. The single tape width is the distance between the inner edge 330 and outer edge 332 of one tape 310 320. The term “spiral width” refers to a width between outer edges of the coils (teeth) 400 when the zipper construction 300 is closed. The spiral width is identified by the legend D in FIG. 2. The distance B in FIG. 2 is a distance from the outer edge 332 to an outer edge of the coils 400 and is less than the single tape width C. The width C—width B is equal to the width of the coils 400. Distance or width A is defined as the exposed surface of one tape 310, 320 when the zipper construction 300 is attached to one edge of fabric. In other words, the outer edge 332 of each tape 310, 320 is securely attached (e.g. stitched) to one edge of the fabric by typically laying the fabric over the tape 310, 320 such that the outer edge 332 is disposed underneath the fabric. The region E in FIG. 2 represents the area or section of the tape 310, 320 that is attached to the fabric thereby leaving the width A of the tape as being the area of the tape 310, 320 that is exposed when the zipper construction 300 is attached to the fabric, etc.

The single tape width C will vary depending upon the particular application; however, in one embodiment, the single tape width C is about ⅝ inch; however, this is merely for one application. When the single tape width C is about ⅝ inch, the width A can be between about ¼ inch to about ⅜ inch. However, it will be understood that as the width C varies, the exposed width A can likewise vary. In general and as described below, in order to obtain the desired transverse stretch, the width A (exposed portion) is about 40 to 60 percent of the width C (entire tape width). Conversely, the width E can be between about 60 to 40 percent of the width C.

The outer edge 332 and inner edge 330 can include a bead or the like to preserve the integrity of the weave and in the case of the inner edge 330 to provide a surface on to which the coils 400 can latch. For example, the inner edge 330 can be a beaded chain stitch edge under the coil 400 so that the coil 400 can attach to the fabric.

Now referring to FIGS. 2-3, the tapes 310, 320 are woven to produce an elastic tape that has increased stretch in the transverse direction (side-to-side). As is known, a weave is formed of the warp which is the set of lengthwise yarns (fibers) through which the weft is woven. Each individual warp thread in a fabric is called a warp end. In the weave pattern shown in FIG. 3, the warp is identified at 370 and the weft is identified at 380. The warp 370 is formed of fibers (yam) that does not have increased elasticity, while the weft 380 is carefully selected so that it has increased elasticity. For example, the warp 370 can be formed of polyester yani (fibers). In one embodiment, the warp 370 is textured polyester 150 ends. The weft 380 is spandex fibers. The latch is similar to the warp in that it is formed of non-elastic fibers (polyester).

In another aspect of the present invention, the applicant has discovered that the zipper construction must be made according to particular steps in order to ensure the integrity and robustness of the zipper construction 300. More particularly, zipper constructions that include spandex fibers should not be dyed post manufacture since the deying process exposes the spandex fibers to elevated temperatures that cause a degradation of the fibers. When a zipper construction including spandex fibers is exposed to the elevated temperatures observed in a polyester deying process, the spandex fibers lose their elasticity and/or can degrade resulting in the zipper construction 300 not having the desired transverse stretch it included prior to deying. Most zipper constructions are dyed and therefore, this deying process adversely impacted the transverse stretch properties of the zipper tape and prevented the zipper tape from having the degree of transverse stretch necessary to achieve the objects of the present invention.

In accordance with the present invention, the warp 370 is pre-dyed prior to the weaving process. For example, the warp 370 can be exposed to a traditional deying process that results in the warp 370 being dyed a selected color, such as black. Since the elastomeric weft fibers are not included in the deying process, they are not exposed to the elevated temperatures used to dye the warp 370. If desired, the elastomeric weft 380 can be dyed using other techniques that do not expose the fibers to elevated temperatures that cause degradation of the fibers. After deying the warp 370 and optionally deying the weft 380, the fibers are introduced into the weave device (e.g., narrow fabrics loom). It will therefore be appreciated that in one aspect of the invention, the zipper tape is formed of pre-dyed warp yarns that are then woven with weft fibers to form the zipper tape shown in FIGS. 2 and 3. In another aspect of the present invention, the weave process is modified so that weft tension is constantly and precisely maintained to allow the spandex to feed properly.

The denier of the warp 370 can be in the range from about 50 denier to about 600 denier depending upon the particular application. For example, a higher denier would be selected for heavier tape/zipper applications, including luggage applications; while, a lower denier (finer) would be selected for clothing. The denier of the weft 380 can range from about 120 denier to about 600 denier, once again depending upon the application.

The weave and construction of the tapes 310, 320 offers increased transverse stretch to accommodate expansion as described above. In one embodiment, the width of the tape stretches greater than 50% relative to its unstretched width. The tape can stretch between about 50% to about 55%, between about 50% and 60%, between about 60% to about 85% (e.g., between about 75% to about 85%). For example, the tape 310, 320 can have a 1 inch width and when stretched, the width of the tape 310, 320 is about 1.85 inch (exemplary stretch ratio is 1:1.85). However, it will be understood that the stretch percentage can be less or greater depending upon the precise application. This can translate to increasing a pant size ½ size from its original size (high hip/low hip dimensions).

The content of the substantially inelastic warp fibers compared to the elastic weft fibers can vary depending upon the particular application. For example, the tape 310, 320 can contain greater than about 65% inelastic warp fibers in one embodiment, greater than about 75% in another embodiment, and about 80% or more in yet another embodiment. Similarly, the tape 310, 320 can contain greater than about 35% elastic weft fibers in one embodiment, greater than about 25% in another embodiment, and about 20% or greater in yet another embodiment. Once again the precise ranges will depend upon the particular application.

EXAMPLE

In one example, each strip (tape) 310, 320 includes warp fibers that are 150 denier black solution dyed textured polyester 150 ends; the weft is 140 denier black solution dyed spandex yarn 40/2 picks and the latch is 70 denier black solution dyed polyester yarn (fiber). Alternatively, the weft is not dyed. In any event, the isolation and deying of the weft separate from the entire zipper construction allows the parameters of the deying process to be carefully controlled to ensure that elasticity of the fibers is not jeopardized. The weight is about 8.056 pounds per one thousand yards. The content is about 80% polyester and about 20% spandex. The weave shown in FIG. 3 is a plain 1/1, latch system II single latch yarn—Muller narrow fabric needle loom. More specifically, tape can be produced on a modified narrow fabrics loom that has been modified to allow for the feeding and weaving of the highly sensitive and stretchable spandex fibers. The weft tension needs to be constantly and precisely maintained in order for the spandex fibers to feed in accurately.

While the invention has been described in connection with certain embodiments thereof, the invention is capable of being practiced in other forms and using other materials and structures. Accordingly, the invention is defined by the recitations in the claims appended hereto and equivalents thereof. 

1. A zipper construction comprising: first and second fabric pieces, wherein each of the first and second fabric pieces includes a first region to which teeth are affixed and a second region that is adjacent the first region, the first region being formed of a substantially inelastic material and the second region is formed of an elastic material, wherein each of the first and second pieces is constructed so that there is a seamless transition from the first region to the second region and the fabric piece is elastic in a transverse direction relative to a length of the fabric piece; and a slider that engages the teeth of the first and second fabric pieces.
 2. The zipper construction of claim 1, wherein the first region is formed of a substantially inelastic material selected from the group consisting of cotton, nylon, polyester, and blends thereof.
 3. The zipper construction of claim 1, wherein the second region is formed of a blend of fibers including elastic fibers.
 4. The zipper construction of claim 3, wherein the blend is selected from the group consisting of cotton and spandex; nylon and spandex; and cotton, nylon and spandex.
 5. The zipper construction of claim 1, wherein the first region has a first weave pattern and the second region has a second weave pattern.
 6. The zipper construction of claim 5, wherein the first weave is inelastic in the transverse direction, while the second weave is elastic in the transverse direction.
 7. The zipper construction of claim 1, wherein the first and second regions are integral with one another.
 8. The zipper construction of claim 3, wherein the blend includes between 25% and 50% by weight of the elastic fibers.
 9. A zipper construction comprising: first and second fabric pieces, wherein each of the first and second fabric pieces includes an inner edge to which teeth are affixed, the first and second fabric pieces being a woven fabric defined by pre-dyed warp fibers formed of a substantially inelastic material and weft fibers that are formed of an elastic material; and a slider that engages the teeth of the first and second fabric pieces.
 10. The zipper construction of claim 9, wherein the warp fibers comprise pre-dyed polyester fibers and the weft fibers comprise spandex fibers.
 11. The zipper construction of claim 9, wherein a stretch ratio as measured by a width of one fabric piece in a relaxed state and a width of the one fabric piece in a stretched state is at least 1:1.85.
 12. The zipper construction of claim 9, wherein each fabric piece is formed of at least 20% elastic weft fibers.
 13. The zipper construction of claim 9, wherein each fabric piece is formed of at least 25% elastic weft fibers.
 14. The zipper construction of claim 9, wherein each fabric piece has an outer edge that defines one edge of an attachment zone that represents a portion of the fabric piece that is covered with an object to which the fabric piece is attached, the attachment zone having a width between about 40 to 60% relative to a total width of the tape in it relaxed state.
 15. The zipper construction of claim 9, wherein the substantially inelastic fibers are dyed at elevated temperatures that would degrade the elasticity of the inelastic weft fibers.
 16. A method for manufacturing a zipper construction comprising the steps of: pre-dyeing warp fibers that are formed of a substantially inelastic material; introducing the pre-dyed warp fibers into a fabrics loom; introducing elastic weft into the fabrics loom under substantially constant weft tension; weaving the warp and weft fibers into a colored zipper tape such that the zipper tape includes at least 20% of the elastic weft, the zipper tape having increased stretch in a transverse direction due to the elastic weft being removed from the pre-dyeing step; attaching teeth along an inner edge of the zipper tape; and aligning two pieces of zipper tape with their inner edges facing one another and engaging a slider with the teeth.
 17. The method of claim 16, wherein the substantially inelastic fibers comprise polyester fibers that are dyed at elevated temperatures that would otherwise damage the inelastic weft fibers. 